Evaluation for endocrine function is a pivotal part of the male infertility workup. Endocrine dysfunction may result from endogenous and exogenous sources. This article describes the traditional roles that the hypothalamic-pituitary-gonadal endocrine axis plays in spermatogenesis and testicular dysfunction, as well as other insults that may contribute to hypospermatogenesis. Recent research into the role alternative hormonal axes play in spermatogenesis and promising new technologies that may correct inborn or acquired endocrinopathies leading to impaired sperm growth and maturation are discussed.